Clinical Neurology in Practice: The Shoulder (Part 1).

Abstract

Background: The shoulder's complex anatomy and biomechanics render it uniquely susceptible to neurological disorders, spanning radiculopathies, plexopathies, and myopathies. Despite its clinical relevance, the shoulder remains understudied in neurological practice, where its dysfunction often serves as an early marker of underlying pathology. A comprehensive understanding of its anatomic, neural, and vascular foundations is essential for accurate diagnosis and management.

Revision summary: This review focuses on the shoulder's osteoligamentous architecture, motor and sensory innervation, vascular supply, and reflexes governing its function. Key topics include: anatomic foundations (glenohumeral and scapulothoracic articulations, ligamentous support, and muscular dynamics), neural control (brachial plexus organization, motor/sensory innervation patterns, and vascular-neural interactions in thoracic outlet syndrome), clinical examination (diagnostic maneuvers and provocative tests to localize nerve root or plexus lesions), and pathologic signatures (scapular dyskinesis, scapula alata, and reflex abnormalities as indicators of neurological dysfunction). Emphasis is placed on practical tools for bedside evaluation, including illustrated anatomic landmarks, reflex testing protocols, and differential diagnostic algorithms.

Conclusion: By synthesizing anatomic precision with clinical applicability, this review equips neurologists to differentiate neurological, orthopedic, and vascular causes of shoulder dysfunction. The framework presented here-combining historical perspectives with evidence-based techniques-aims to refine diagnostic accuracy and inform targeted interventions. Part 2 will explore specific neurological pathologies (eg, central syndromes, myopathies, and postinjury complications) to complete this comprehensive resource for clinical practice.